1. Field of the Invention
This invention relates to a webbing support apparatus to be used in a seat belt device installed in a vehicle and by which supporting height of a webbing can be varied in response to a physical size of an occupant.
2. Prior Art
A webbing support apparatus of this type is used in a three-point supporting seat belt apparatus of which webbing is of a continuous type. A slip point of the webbing support apparatus is movable in a vertical direction where an intermediate portion of the webbing in a longitudinal direction serves as an upper end of a shoulder webbing portion which is bent and supported.
The conventional webbing support apparatus as described above has been proposed to provide a construction which a moving member is arranged to be guided by a guide rail fixed to a body of a vehicle and can be moved in a vertical direction and then the above-mentioned slip joint is fixed. The moving member is restricted by restricting means against the guide rail under a condition in which its downward movement is prohibited at each of a plurality of vertical positions at the guide rail. The restricted condition can be released by the operating means arranged at the moving member so as to enable a height position of the moving member to be varied (for example, Japanese Utility Model Publication No. 60-40370 and Japanese Patent Application Laid-Open No. 58-501586).
However, since the moving member receives a winding load of the webbing take-up apparatus or its weight or a weight of a slip joint etc., the moving member is apt to simultaneously be moved downwardly along the guide rail when the restricted state is released.
Due to this fact stated above, in particular, in case that a supporting height of the webbing is tried to be lowered, the moving member can not be stopped at a predetermined position and so it is sometimes found that the moving member may move down to a lower moving limitation in contrast to the will of an operator.